206 FaiKjicuJal Properties of Certain Spray-Jla!(h 



without fungicidal effect ; on the fifth day after sj)raying all the patches 

 were as powdery as before. 



With 0-032 % polysulphide sulphur the fungicidal action was quite 

 evident, and the identity of action of the two solutions was well seen. 

 On the two leaves, each at the fourth and fifth nodes, the two solutions 

 did not prevent most of the powdery patches from reforming clustered 

 conidiophores by the fifth day; with regard to the other leaves there 

 were a few dead patches on each leaf, and clustered conidiojjhores 

 regrowing from the edge of most patches — the amount of growth of 

 the mildew being the same for the two solutions. 



With 0-0.J3 % polysulphide sulphur Solution VIII proved very 

 slightly more potent than Solution XI with 0-0.52 % polysulphide 

 sulphur: the dift'erence, however, was so slight (considering the variable 

 l)ioIogical factors concerned) that it cannot be held to impugn the 

 identity in fungicidal action of the two solutions. 



With 0-077 % and 0-078 % polysulphide sulphur the action was 

 fungicidal; from the third day onward the sprayed patches remained 

 white and persistently sterile until they died. 



Comparison of Ammonium, 'polysulphide Solvfions XI and IX 

 (both solutions with 1 % soap). 



There was strong similarity in the action of these two solutions. 

 Solution XI with 0-031 % polysulphide sulphur was apparently slightly 

 stronger in fungicidal action than Solution IX with 0-029 % . With 

 0-039 % and 0-036 % respectively, Solutions XI and IX proved to be 

 identical in action. In Experiments 3 and 4, Solution XI, with 0-052 % 

 was very sHghtly stronger in fungicidal action than Solution IX with 

 0-048 %. With 0-078 % and 0-072 % respectively. Solutions XI and 

 IX both proved fungicidal. 



Co)Hparison of Ammonia m polysulphide Sohitions V and VII 

 (bcth solutions with 1 % soap). 



At the only strength, viz., containing 0-077 % polysulphide sulphur, 

 at which these solutions were compared, they proved identical in 

 fungicidal action, as the following details show. . 



Sol. V Sol. VII 



No. of leaf No. of leaf* 



Fungicidal 4,5.0,7,8,10,11,12 4,5,0,7,10,11,12 



Very nearly fungicidal ... 1,2 1,2 



Not quite fungicidal ...... 9 9 



* leaf 8 died. 



